Eggs are a very healthy and nutritious foodstuff, but what about the shells? While many people will simply bin or compost their eggshells, once the white and yolk have been removed, there are many other uses for them. This Entry describes a few.

In The Garden

Slugs do not appreciate having to travel over jagged and rough terrain in order to get a meal. Many gardeners find that simply placing a ring of broken eggshell pieces around prized plants helps to keep the little blighters away. However, you could always employ a friendly neighbourhood hedgehog to eat the slugs instead.

Crushed eggshells can also be used to regulate the acidity of a garden wormery.

Growing cress is a simple task that even very young children can take part in. For this project, the eggshell needs to be fairly whole, possibly from your boiled egg at breakfast time. As well as a suitable eggshell, you will need cress seeds and some cotton wool. Put the wet cotton wool ball into the eggshell and then sprinkle in the seeds. Place the eggshell on a sunny window sill. The shoots of cress should appear in three to five days, and can be eaten once the leaves are fully opened. Cress is tasty in salads and also in egg sandwiches.

Decoration

As a child, you probably remember painting hard boiled eggs at Easter time, but this is not the only way in which eggshells can be used decoratively. Try the following activity with your younger family members. Take three or four eggshells and paint them each a different colour. Once the paint has dried, put the eggshells in to a sandwich bag. This next stage should be done by an adult. Take a rolling pin or similar object, and roll it over the eggshells once to break them into small pieces. Alternatively, you can place two or three eggshells in a bowl, add a generous amount of food colouring, then crush the eggshells with a spoon, You will need a separate bowl for each colour, but this method may appeal to parents of younger children. Next you will need a plain-coloured picture frame, preferably a couple of inches (5 cm) wide. Cover this with PVA glue, and arrange the coloured pieces of eggshell on it to create a multicoloured mosaic effect.

Blown eggs can be made into interesting mobiles to hang around your house. To blow an egg, simply pierce each end with a long needle or other sharp object and then blow out the contents. This must be done carefully to ensure the eggshell stays whole. You can now thread string through the eggshell and decorate it however you choose. You could have a family tree, with each member represented by an eggshell portrait, or you could add papier mache shapes to your eggshell to turn it into a fish, or a plane, or a spaceship – it is entirely up to you. If blowing eggs proves too tricky, you could always make a mobile out of eggshell halves.

Other Ideas

Some people believe the superstition that eggshells, if not crushed, can be used as boats by witches. This means that all eggshells must be holed or crushed before they can be disposed of or used for craft activities.

Finely crushed eggshells are useful when making wine. The tiny pieces of shell absorb the carbon dioxide which makes the wine go cloudy, and then float to the top of the wine to release the gas. This forms part of the brewing process of some country and amateur winemakers.

If you like to make home-made cat food, then you can include a small amount of finely crushed eggshell to ensure that your feline friend gets the calcium that they would otherwise get from the bones of small animals that they would eat in the wild.

There are many other things you can do with your eggshells. We have listed a few just to get you started, but maybe you will invent something new. The next time you are baking a cake or frying an egg, don't just throw the eggshell away; use it instead to make something interesting.